(1) Field of the Invention
This invention relates to novel quaternary phosphonium salts. More particularly, it relates to quaternary phosphonium salts in which one or more of the phosphorus substituents bears a carbamate group attached through its nitrogen atoms.
(2) Description of the Prior Art
Heretofore, it was not generally known that quaternary phosphonium salts bearing nitrogen-containing groups are capable of existence, because the amines used in their preparation cause the phosphonium salt to rupture, displacing formaldehyde and a tertiary phosphine. The sole exceptions are the arylaminoalkyl phosphonium salts, described by A. W. Frank and G. L. Drake, Jr., in U.S. Pat. No. 3,987,098 (1976), which retain their quaternary structure by virtue of the weak basicity of the aromatic amines.